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Investments - Summary of Amortized Cost and Estimated Fair Value of Available-for-Sale Investments, Excluding VIE Investments (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024	Sep. 30, 2024
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position	$ 61,582	$ 119,024
Debt Securities, Available-for-sale, Allowance for Credit Loss	0	0	$ 0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	1,181	260
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	7,750	51,012
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	71	792
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	53,832	68,012
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	2,616	4,559
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	2,687	5,351
Debt Securities, Available-for-Sale	426,926
Debt Securities, Available-for-sale, Amortized Cost	428,432	289,712
Debt Securities, Available-for-Sale, Current	426,926	284,621
Short-term Investments [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position	0	0
Debt Securities, Available-for-sale, Allowance for Credit Loss	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	10	13
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	0	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	0	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	0	0
Debt Securities, Available-for-Sale	295,825	127,601
Debt Securities, Available-for-sale, Amortized Cost	295,815	127,588
Fixed Income Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position	61,582	119,024
Debt Securities, Available-for-sale, Allowance for Credit Loss	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	1,171	247
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	7,750	51,012
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	71	792
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	53,832	68,012
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	2,616	4,559
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	2,687	5,351
Debt Securities, Available-for-Sale	131,101	157,020
Debt Securities, Available-for-sale, Amortized Cost	132,617	162,124
Fixed Income Securities [Member] | Municipal Bonds [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position	6,509	12,624
Debt Securities, Available-for-sale, Allowance for Credit Loss	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	100	7
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	318	6,042
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	15	112
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	6,191	6,582
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	264	458
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	279	570
Debt Securities, Available-for-Sale	11,510	14,083
Debt Securities, Available-for-sale, Amortized Cost	11,689	14,646
Fixed Income Securities [Member] | Corporate Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position	36,124	70,396
Debt Securities, Available-for-sale, Allowance for Credit Loss	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	590	107
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	3,269	23,784
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	13	269
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	32,855	46,612
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	2,167	3,636
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	2,180	3,905
Debt Securities, Available-for-Sale	70,690	89,192
Debt Securities, Available-for-sale, Amortized Cost	72,280	92,990
Fixed Income Securities [Member] | US Government Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position	16,076	30,737
Debt Securities, Available-for-sale, Allowance for Credit Loss	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	398	98
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	3,012	15,919
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	34	344
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	13,064	14,818
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	171	465
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	205	809
Debt Securities, Available-for-Sale	39,171	40,995
Debt Securities, Available-for-sale, Amortized Cost	38,978	41,706
Fixed Income Securities [Member] | Residential Mortgage-Backed Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position	1,722	2,446
Debt Securities, Available-for-sale, Allowance for Credit Loss	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	43	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	0	2,446
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	29
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	1,722	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	14	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	14	29
Debt Securities, Available-for-Sale	3,294	2,446
Debt Securities, Available-for-sale, Amortized Cost	3,265	2,475
Fixed Income Securities [Member] | Collateralized Debt Obligations [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position	390	655
Debt Securities, Available-for-sale, Allowance for Credit Loss	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	15	13
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	390	655
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	2
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	0	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	0	2
Debt Securities, Available-for-Sale	2,319	3,142
Debt Securities, Available-for-sale, Amortized Cost	2,304	3,131
Fixed Income Securities [Member] | Asset-backed Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position	0	1,428
Debt Securities, Available-for-sale, Allowance for Credit Loss	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	24	14
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	0	1,428
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	2
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	0	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	0	2
Debt Securities, Available-for-Sale	2,298	5,061
Debt Securities, Available-for-sale, Amortized Cost	2,274	5,049
Fixed Income Securities [Member] | Commercial Mortgage Backed Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position	761	738
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	761	738
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	9	34
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	0	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	9	34
Debt Securities, Available-for-Sale	1,819
Debt Securities, Available-for-sale, Amortized Cost	1,827
Fixed Income Securities [Member] | Collateralized Mortgage Backed Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Allowance for Credit Loss	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	1	8
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	9	34
Debt Securities, Available-for-Sale	1,819	2,101
Debt Securities, Available-for-sale, Amortized Cost	1,827	$ 2,127
Fixed Income Investments And Other Investments [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	$ 2,687

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Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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